CHAPTER X. 

 THE DOLPHINS 



FAMILY, DELPHIN1DAE 



THE family Delphinidae may be thus defined : 

 Of small to moderate size. Teeth as a rule 

 numerous, and in both jaws. Anterior ribs (5-8) 

 two-headed, posterior with tuberculum only ; sternal 

 ribs ossified. Palatines meeting for a greater or less 

 extent in the middle line. 



This family of whales comprises, as the name de- 

 notes, those Cetacea which are commonly known as 

 Dolphins and Porpoises. There are no giants among 

 the Delphinidae, save only Orca* the Killer whale, 

 which may grow to a length of over 20 feet ; but 

 nothing of a colossal size is attained to by any 

 member of the family Delphinidae. 



The skull of all these whales is characterised by 



* The mysterious Delphinus coronatus of M. de Freminville may, 

 however, be mentioned as a possible exception. It is 30-36 feet long, 

 with a relatively small head, which would suggest a Mesoplodqn were it 

 not for the numerous teeth in both jaws. The " bee fort pointu " and the 

 dorsal fin nearer the tail than the head seem to forbid the notion that it 

 is an Orca. What is it? It comes from Spitzbergen shores. 



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